1. Technical Field of the Invention
This invention relates to a tire removal machine.
More specifically, the invention relates to a type of tire removal machine comprising a fixed bed, close to which there are provided two working stations, one for tire bead release from the wheel rim and one for removing the tire from and for mounting the tire on the wheel rim, and comprising a wheel rotation unit having a motorized mandrel provided with means for rigidly locking the wheel rim coaxially to the mandrel axis. The mandrel is carried by support means swivelling between two positions: a first position in which the mandrel is horizontal and the wheel lies in the bead release station, and a second position in which the mandrel is brought into a vertical position and the wheel lies in the mounting/removal station. In the bead release station, suitable bead release means are provided for operating on the wheel carried by the mandrel, the other station being provided with suitable means for mounting/removing the tire on and from the wheel rim.
2. Prior Art
This type of machine has various advantages over more traditional machines with a fixed horizontal work bench on which a vertical mandrel is provided; in particular, positioning the wheel on the mandrel is manually much simpler and less fatiguing, as the wheel does not have to be raised manually onto the work bench.
However this type of machine requires considerable space, mainly because it involves two separate working stations. This is a very considerable drawback because the premises where these machines are used are usually relatively small. An object of the present invention is to provide a machine of the aforesaid type, in which the space occupied by the machine is much smaller than known machines of the same type.
This and further objects are attained by the present invention wherein the machine of the invention comprises:
a working station;
a fixed bed disposed on the rear side of the working station;
for rotating a wheel, a unit carried by a support bracket connected to the fixed bed in such a manner as to be able to swivel about a horizontal axis passing through the station, and comprising, carried by and projecting from said support bracket, a motorized mandrel which is provided with means for rigidly locking the wheel rim and is disposed with its axis perpendicular to and cutting or nearly cutting the swivel axis, so that the tire of the wheel carried by the mandrel is traversed, in a virtually central position, by the swivel axis of the support bracket;
means for swivelling the support bracket between two operative positions, in the first of which the axis of rotation of the wheel is disposed in a horizontal position, and in the second of which the axis of rotation of the wheel is disposed in a vertical position;
bead release means connected to the fixed bed in such a manner as to be able to assume a working position, in which they are operative on the wheel positioned in the working station in the first operative position, and a second retracted position alternately;
tire mounting/removal tool holder means connected to the fixed bed in such a manner as to be able to assume a working position, in which they are operative on the wheel positioned in the working station in the second operative position, and a second retracted position alternately.
In passing from one operative position to the other, the wheel swivels about a virtually diametrical axis passing virtually through the geometrical centre of the wheel, and consequently, although changing orientation (its axis passes from horizontal to vertical and vice versa), it is always maintained in the same working station.